Optimal stability for trapezoidal-backward difference split-steps

The marginal stability of the trapezoidal method makes it dangerous to use for highly non-linear oscillations. Damping is provided by backward differences. The split-step combination (αΔt trapezoidal, (1 – α)Δt for BDF2) retains second-order accuracy. The ‘magic choice’ a = 2 – √2 allows the same Ja...

全面介绍

书目详细资料
Main Authors: Dharmaraja, Sohan, Wang, Yinghui, Strang, Gilbert
其他作者: Massachusetts Institute of Technology. Department of Mathematics
格式: 文件
语言:en_US
出版: Oxford University Press 2013
在线阅读:http://hdl.handle.net/1721.1/80879
https://orcid.org/0000-0001-7473-9287
实物特征
总结:The marginal stability of the trapezoidal method makes it dangerous to use for highly non-linear oscillations. Damping is provided by backward differences. The split-step combination (αΔt trapezoidal, (1 – α)Δt for BDF2) retains second-order accuracy. The ‘magic choice’ a = 2 – √2 allows the same Jacobian for both steps, when Newton's method solves these implicit difference equations. That choice is known to give the smallest error constant, and we prove that a = 2 – √2 also gives the largest region of linearized stability.